Highest temperature in Paris on July 20?

Platform comparison

Market context

Paris will face its highest recorded temperature on 20 July 2026 at the Paris-Le Bourget Airport Station, the specific metric determining this market’s outcome. On Polymarket today, the YES contract for any temperature range is priced at 0% implied probability, suggesting the crowd believes the event is impossible or that the market has already resolved against it, despite the settlement window ending later this month. This zero pricing is unusual for a weather event with a future date, often indicating a technical glitch, a resolved outcome not yet reflected in the UI, or a consensus that the specific range queried is physically unattainable.

Historically, July heatwaves in France have pushed Paris temperatures above 40°C, with Météo-France reporting a current heatwave reaching 40°C in early July 2026 that may persist until mid-month [1]. Forecasts for the 2026 heatwave suggest daytime highs could reach 42°C in hotspots, though Paris and northern areas typically record slightly lower peaks than southern cities like Marseille [2]. If the current heatwave pattern continues or intensifies, temperatures on 20 July could easily exceed 35°C, making a 0% probability for any range logically inconsistent unless the market is betting on a specific, narrow, and extremely low range that is already deemed impossible.

Traders should monitor Météo-France’s daily bulletins for updates on the heatwave’s duration and intensity, as the agency notes considerable uncertainty regarding its end date [1]. The primary catalyst is the official temperature reading from Wunderground for Paris-Le Bourget on 20 July, which will settle the contract using USDC on the Polygon network via conditional tokens. Any sudden shift in forecast models indicating a break in the heatwave before 20 July would be the key signal to reassess the 0% pricing, as the current consensus appears to ignore the established trend of extreme heat in the region.

Sources: 1 · 2

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.